Server Response 

A server response module for use with Node / ExpressJS.

The goal of this module is to standardize responses from JSON enabled servers. Each response sent contains the statusCode, statusMessage, statusDescription and result.

``javascript
{
"statusCode": 200,
"statusMessage": "OK",
"statusDescription": "Request succeeded without error",
"result": {}
}
`

#### So why is this a big issue?

Because the server responses have the potential to travel between multiple chained service endpoints each of which might otherwise have its own idea of how a response should be formatted. Using this module offers multiple processes the opportunity to easily standardize on a uniform response format.

Other client, servers, and services which receive the formatted response can always depend on knowing where to retrieve the HTTP status (statusCode) and where to find the actual response body (result).

Installation

`shell
$ npm -i install fwsp-server-response
`

Usage

The easiest way to use server-response is to use one of the provided responders. The first parameter res is a Node HTTP response object or an ExpressJS response object. This allows serverResponse to send a response back through the provided res object.

`javascript
serverResponse.sendOk(res, {
result: {
key: value
key: value
}
})
`

In the example above the data object sent provided is merged with the following object to build a response:

`javascript
{
"statusCode": 200,
"statusMessage": "OK",
"statusDescription": "Request succeeded without error",
"result": {
key: value
key: value
}
}
`

> Note: ServerResponse automatically fills the statusCode, statusMessage and statusDescription fields based on the response member used. In the above example we're sending an HTTP_OK response using the sendOk member function.

So in the above example, the provided .result it merged in. This means that you can also overwrite the statusCode, statusMessage and statusDescription fields as well. However, it's recommended that only the statusDescription be modified in order to maintain consistency throughout a distributed system.


`javascript
serverResponse.sendInvalidRequest(res, {
statusDescription: 'The to field is missing from your request'
})
`

You can also add and override HTTP headers by providing a headers sub-object:

`javascript
serverResponse.sendInvalidRequest(res, {
headers: {
'Content-Type': 'text/plain',
'X-Powered-By': 'myCoolService/1.0'
},
result: {
key: value
key: value
}
})
`

List of responders

#### enableCORS
Enable / Disable CORS support
`javascript
/**
* @name enableCORS
* @summary Enable / Disable CORS support
* @param {boolean} state - true if CORS should be enabled
*/
`

#### createResponseObject
Create a data response object.
`javascript
/**
* @name createResponseObject
* @summary Create a data response object.
* @description This creates a consistently formatted HTTP response. It can be used
* with any of the server-response send methods in the data param.
* @param {number} httpCode - HTTP code (Ex. 404)
* @param {object} resultPayload - object with {result: somevalue}
* @return {object} response - object suitable for sending via HTTP
*/
createResponseObject(httpCode, resultPayload)
`

#### sendResponse
Send a server response to caller
`javascript
/**
* @name sendResponse
* @summary Send a server response to caller.
* @param {number} code - HTTP response code
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendResponse(code, res, data)
`

#### sendOk
Send an HTTP_OK server response to caller
`javascript
/**
* @name sendOk
* @summary Send an HTTP_OK server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendOk(res, data)
`

#### sendCreated
Send an HTTP_CREATED server response to caller
`javascript
/**
* @name sendCreated
* @summary Send an HTTP_CREATED server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendCreated(res, data)
`

#### sendMovedPermanently
Send an HTTP_MOVED_PERMANENTLY server response to caller
`javascript
/**
* @name sendMovedPermanently
* @summary Send an HTTP_MOVED_PERMANENTLY server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendMovedPermanently(res, data)
`

#### sendNotFound
Send an HTTP_NOT_FOUND server response to caller
`javascript
/**
* @name sendNotFound
* @summary Send an HTTP_NOT_FOUND server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendNotFound(res, data)
`

#### sendInvalidRequest
Send an HTTP_BAD_REQUEST server response to caller
`javascript
/**
* @name sendInvalidRequest
* @summary Send an HTTP_BAD_REQUEST server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendInvalidRequest(res, data)
`

#### sendInvalidSession
Send an HTTP_BAD_REQUEST server response to caller
`javascript
/**
* @name sendInvalidSession
* @summary Send an HTTP_BAD_REQUEST server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendInvalidSession(res, data)
`

#### sendInvalidUserCredentials
Send an HTTP_UNAUTHORIZED server response to caller
`javascript
/**
* @name sendInvalidUserCredentials
* @summary Send an HTTP_UNAUTHORIZED server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendInvalidUserCredentials(res, data)
`

#### sendRequestFailed
Send an HTTP_REQUEST_FAILED server response to caller
`javascript
/**
* @name sendRequestFailed
* @summary Send an HTTP_REQUEST_FAILED server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendRequestFailed(res, data)
`

#### sendDataConflict
Send an HTTP_CONFLICT server response to caller.
`javascript
/**
* @name sendDataConflict
* @summary Send an HTTP_CONFLICT server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendDataConflict(res, data)
`

#### sendTooLarge
Send an HTTP_TOO_LARGE server response to caller
`javascript
/**
* @name sendTooLarge
* @summary Send an HTTP_TOO_LARGE server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendDataConflict(res, data)
`

#### sendTooManyRequests
Send an HTTP_TOO_MANY_REQUEST server response to caller
`javascript
/**
* @name sendTooManyRequests
* @summary Send an HTTP_TOO_MANY_REQUEST server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendTooManyRequests(res, data)
`

#### sendServerError
Send an HTTP_SERVER_ERROR server response to caller
`javascript
/**
* @name sendServerError
* @summary Send an HTTP_SERVER_ERROR server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendServerError(res, data)
`

#### sendInternalError
Alias for sendResponseServerError
`javascript
/**
* @name sendInternalError
* @summary Alias for sendResponseServerError
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendInternalError(res, data)
`

#### sendMethodNotImplemented
Send an HTTP_METHOD_NOT_IMPLEMENTED server response to caller
`javascript
/**
* @name sendMethodNotImplemented
* @summary Send an HTTP_METHOD_NOT_IMPLEMENTED server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendMethodNotImplemented(res, data)
`

#### sendConnectionRefused
Send an HTTP_CONNECTION_REFUSED server response to caller
`javascript
/**
* @name sendConnectionRefused
* @summary Send an HTTP_CONNECTION_REFUSED server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendUnavailableError(res, data)
`

#### sendUnavailableError
Send an HTTP_METHOD_NOT_IMPLEMENTED server response to caller
`javascript
/**
* @name sendUnavailableError
* @summary Send an HTTP_METHOD_NOT_IMPLEMENTED server response to caller.
* @param {object} res - Node HTTP response object
* @param {object} data - An object to send
* @return {object} res - Returns the (res) response object when in test mode, else undefined
*/
sendUnavailableError(res, data)
`

Exported HTTP codes

`
ServerResponse.HTTP_OK = 200;
ServerResponse.HTTP_CREATED = 201;
ServerResponse.HTTP_MOVED_PERMANENTLY = 301;
ServerResponse.HTTP_BAD_REQUEST = 400;
ServerResponse.HTTP_UNAUTHORIZED = 401;
ServerResponse.HTTP_REQUEST_FAILED = 402;
ServerResponse.HTTP_NOT_FOUND = 404;
ServerResponse.HTTP_METHOD_NOT_ALLOWED = 405;
ServerResponse.HTTP_CONFLICT = 409;
ServerResponse.HTTP_TOO_LARGE = 413;
ServerResponse.HTTP_TOO_MANY_REQUEST = 429;
ServerResponse.HTTP_SERVER_ERROR = 500;
ServerResponse.HTTP_METHOD_NOT_IMPLEMENTED = 501;
ServerResponse.HTTP_CONNECTION_REFUSED = 502;
ServerResponse.HTTP_SERVICE_UNAVAILABLE = 503;
``